Train and rail cases reward speed more than almost any other kind of injury claim, for two reasons. First, railroads and transit agencies respond immediately — they send investigators and claims representatives to a scene within hours, and they control the key evidence, including the train's event recorder, crossing-signal data, and maintenance records.
That evidence can be altered, overwritten, or simply become hard to obtain if no one moves to preserve it. Getting your own investigation started, and formally demanding that the railroad preserve its evidence, levels a field that otherwise heavily favors a well-resourced defense that got there first.
Second, if a public transit agency is involved, a short government-claim deadline applies — often just months. Between the evidence and the deadline, the early days after a train accident are critical, which is why a prompt, free review is worth getting right away.